<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <script src="bootstrap/js/jquery/2.0.0"></script>
    <link href="bootstrap/css/bootstrap/3.3.6/bootstrap.min.css" rel="stylesheet">
    <script src="bootstrap/js/bootstrap/3.3.6/bootstrap.min.js"></script>

    <title>Bootstrap</title>
    <style>
        div{
            text-align: center;
        }
        #sel {
            width: 50%;
            margin: auto;
        }
        div.container, div.row {
            background-color: lightgray;
            border: 1px solid gray;
            text-align: center;
        }
    </style>
</head>

<body>
    <div>
        <br><button class="btn">原始样式按钮</button><br><br>
        <button class="btn btn-default">默认按钮</button><br><br>
        <button class="btn btn-primary">提交按钮</button><br><br>
        <button class="btn btn-success">成功按钮</button><br><br>
        <button type="button" class="btn btn-info">信息按钮</button><br><br>
        <button type="button" class="btn btn-warning">警告按钮</button><br><br>
        <button type="button" class="btn btn-danger">危险按钮</button><br><br>
        <button type="button" class="btn btn-link">表现为链接</button><br><br>
        <button type="button" class="btn btn-lg">大一点的按钮</button><br><br>
        <button type="button" class="btn btn-sm">小一点的按钮</button><br><br>
        <button type="button" class="btn btn-block">宽屏按钮</button><br><br>
        <button type="button" class="btn active">激活状态按钮</button><br><br>
        <button type="button" class="btn disabled">领红包</button><br><br>
        <button type="button" class="btn disabled btn-danger btn-xs">发红包</button><br><br>
    </div>
    <div>
        <img src="https://how2j.cn/example.gif" class="img-rounded">
        <img src="https://how2j.cn/example.gif" class="img-circle">
    </div>
    <div>
        <select name="" id="sel" class="form-control">
            <option value="">Java</option>
            <option value="">Html</option>
            <option value="">iOS</option>
        </select>
    </div>
    <div>
        <span class="text-warning">警告文本</span>
        <span class="text-danger">危险操作</span>
    </div>
    <div>
        <p class="bg-primary">强调背景色</p>
        <p class="bg-success">成功背景色</p>
    </div>
    <div>
        <button class="close">&times;</button>
        <span class="caret"></span><br>
        <span class="pull-left">文字浮动到左边</span>
        <span class="pull-right">文字浮动到右边</span><br>
        <div class="show">显示1</div>
        <div class="hidden">显示2</div>
        <div class="show">显示3</div>
    </div>

    <div class="container">
        <div class="row">
            <div class="col-xs-1 ">收入</div>
            <div class="col-xs-1 ">支出</div>
        </div>
        <div class="row">
            <div class="col-xs-1 ">2000元</div>
            <div class="col-xs-1 ">1405元</div>
        </div>
    </div>
</body>

</html>